Automatic toaster



Oct. 11, 1938. R. SARD ESON AUTOMATIC TOASTER Filed April 14, 1937 2 Sheets-Sheet 1 Isl I65 Ill mas

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Oct. 11, 1938. R. SARDESON 7 AUTOMATIC TOASTER Filed April 14, 1957 2 Sheets-Sheet 2 w A wm y ITS e e n d r e. o vafl m A e1 ,o Em

Patented Oct. 1 1, 1938 UNITED, STATES AUTOMATIC roasrna Robert Sardeson, Minneapolis, Minn, assignor to McGraw Electric Company, Chicago, 111., a. corporation of Delaware Application April 14,1937, Serial No. 136,826 18 Claims. (oi. 219-19) My invention relates to electric toasters and particularly to thermallyresponsive timing mechanisms for electric toasters. An object of my invention is to provide a unitary thermally-responsive timing mechanism adapted to cooperate with, a toaster to vary the du'ration of an operating period of a toaster in accordance with temperature changes therein.

Another object of my invehtion is to provide variable speed mechanical timer with a single speed-adjusting member adapted to be engaged and -actuated'by manual meansas well as by thermally-actuable means. 3

Another object of my invention is to provide a variable speed mechanical timer having a speed Q" adjusting member adapted to be manually adjustable while maintaining constant the relative positions of a thermostat and of the speed ad- Justing member.

Another object of my invention is to provide a 'variablespeed mechanical timer adapted to constitute the sole support fora cooperating control ,thermostat normally free of any externally applied mechanical stress.

Another object of my invention is to :provide an automatic toaster including a mechanical timer and a thermally-actuable element. coopcrating therewith to vary the operating period of thetoaster, in which the thermal element is so positioned as to be subjected to relatively high temperature radiant heat transmitted thereto by a plate of relatively small mass and thickness and having high heat-absorbing and heatradiating capacity." H

Other objects of my invention will either be pointed out in the description of one form now preferred byeme, or will ,be apparent from such 4 description. p V g In the drawings, Figure 1 is a view, mainly irrside elevation, but with portions of the structure cut away, oi." a toaster embodying my invention,. f

Fig. 2 is a view, in side' elevation, of a unitary thermally-controlled timing mechanism on an enlarged scale. a i

Fig. 3' is a fragmentary perspectivenview on an enlarged scale, showing the relative positions of. certain parts ofthe toaster structure,

x Fig. 4 is a fragmentary interior view, in side elevation, of a party of the timing mechanism,

Fig.5 is a view, in side elevatiohwith parts broken away and partially in section, or a toaster embodying ,my invention asrseen fromvtl'ie side" opposite to that of. Fig. 1,

Fig. dis 'a viewxin front elevation of a toaster I the art, these walls cooperating to define a toastsubstantially longitudinally thereof, there being a embodying my invention with a part of the front wall of the casing br oken away, and,

1 Fig. 7 is a fragmentary view, on an enlarged scale, taken on. the line 1-4 of Fig. 1.

A toaster assembly of the vertical oven type designated generally by! includes a skeleton base frame I! which may be made of molded material and athin base plate l5 secured thereto at the ,top face thereof, which plate may be held by a plurality of machine screws ii, any 9 desired number of which may be used.

The assembly includes further a casing I 9 comprising two side walls and a front and a rear wall together with a cover 2| which may have interiltting engagement with the inturned top edge of casing IS. in a manner well known in the art. The casing l9 may be held against the upper surface of base plate l5 as by a plurality of short machine screws 23, although I do not desire to be limited to such securing and holding means since they constitute no part of my present "invention. The toaster includes a Jront intermediate wall 26, a rear intermediate wall 21 and two intermediate side walls or bafile plates 29, all. in a manner now well known in ing chamber within the casing l9. I A plurality of heating elements extend sub-' stantially vertically within the toaster casing and pairof such electric heating elements for each slice of bread on which the toaster is adapted to operate. Each heating element includes one orzmore thin plates ll of electric insulating materia'lfsuch asgmica, on one face of which there is mounted a resistor element" of wire or of strip. Substantially all of the length of resistor 33 is located on that face or side of its. supporting plate of-electric-insulating material facing the cooperating supporting plate so that a slice of 40 bread positioned between such two cooperating heating elements will be subjected to heat from 'substantially all of the length of the resistor. It 'may be here pointed out that the amount of- .energy'translated' into heat in the respective.

heating elements is such that the resistor will operate at dull redheat, that is, the slice of bread being toasted will be subjected to relatively high temperature radiant heat.

Thelbwer. edges of the plates 3| of electricinsulating material may be positioned by upstanding lugs 35- punched out of base plate l5 and the upper edges of these sheets of electricinsulating material may be held in proper operative positions relatively to each other by depending flanges in horizontally-extending frame members 31 and by hook portions of guard wires 39 having interfltting engagement with the respective frame members 31, all in a manner well known in the art.

The toaster assembly includes also a plurality of inner vertical standards 4| and a pair of outer standards 43 positioned in a mechanism chamber 45 which is defined by the front intermediate wall 25 and the front wall of casing I9. A carriage 41 is vertically movable on the pair of inner standards 4| and is adapted to cause a slider 49 on the left hand standard 43 and a slider 5| on the right hand standard 43 to be moved downwardly when an operator presses on a knob 53 which is suitably mounted on and secured to a forwardly extending portion 55 on a member 51 which .is loosely mounted on carriage 41.

Bread supports" are vertically movable between the respective pairs of electric heating elements hereinbefore described, it being evident from Fig. 6 of the drawings that I have illustrated a two-slice toaster in whichthe cover 2| is provided with a pair of openings 3| for insertion and removal of slices of bread. It is obvious that the top frame members 31 are provided with openings registered with the respective openings 6|, all in a'manner now well known in the art. The guard wires 39 extend through openings in the bread slice supports 59. The bread slice supports are operatively connected by a rod 93 (see Fig. 6 of the drawings) and are thereby secured to the respective sliders 49 and 5| so that downward pressure by an operator onknob 53 will'cause downward movement of carriage 41, member 51, sliders 49 and 5| and bread'slice supports 59.

Means to control the supply of electric energy to the heating elements through a twin conductor cord includes a circuit-controlling switch comprising a fixed contact member 61 insulatedly mounted on the front intermediate wall 25 and a contact arm 69 alsoinsulatediy mounted on the front intermediate wall 25 and pivotally supported thereon on a bracket 1|.

Means for causing turning movement of arm 69 coincident with vertical movement et the carriage and ,the sliders includes a slotted plate 13 'secured at one side of and to slider 49, arm

" 6 59 being provided with a rod 15 adapted to have one end fitting in slotted plate 13, the shape of the slot being shown in Fig. 5 of the drawings.

Means for biasing the switch to open position and the bread slice supports to their upper or non-toasting position includes a bell crank lever cornprising a substantially horizontally extending arm 11 and a depending arm 19, which bell crank lever is pivotally supported at 9| on the rear intermediate plate 21. A helical spring 93 has one end connected to the outer end of arm 19 and its other end hooked into a part of base plate I5, also in a manner well known in-the art. The forward end of arm .-11 is. slotted as shown at 95 in Fig. 5 of the drawings, the rod 93 being positioned in said slotted forward end so that downward movement of carriage 41 and'the associated parts will cause movement of arms 11. and 19 in a clockwise direction (as seen in Fig. 5) downward movementbf thebread slice supports and closing of the switch.

Means for holding the switch closed and the bread slice supports in their lower or toasting position includes a pr ijection 81 on slider 5| which projection is adapted to fit below the lower end of a latch arm 99 which latch arm is pivotally mounted on the structure of a mechanical timer 9|.

This timer includes a helical spring 93 of substantially the type used in ordinary clocks, which spring is adapted to be wound up on a spring 5 shaft 95 which shaft has a pinion 91 mounted fixedly thereon, which ratchet wheel ,is engaged by a rack bar 99 havinga laterally extending lug IOI, which lug is adapted to be operatively engaged by a member I03 of substantially in- 10 verted V-shape secured to or being a part of carriage 41 downwardly by pressure on the knob 53 he therefore not only moves downwardly the bread slice supports and closes the control switch but also winds up ,the spring 93, all of this being 5 already wellknown in the art.

The timer 9| includes a gear train shown generally only in Fig. 2 of the drawings, which gear train ends in an eccentric I05, which eccentric is adapted to cause oscillating movement of an osgo cillator I01 which latter is pivotally mounted as at I09 on a pivotally mounted lever arm III. This lever arm III is fixedly mounted on a pin 3 supported by the side plates of timer 9|. A balance wheel H5 is adapted .tobe oscillated by member I01 through a spring II1, it being understood that oscillator I01 can be moved from the position shown in Fig. 4 of the drawings to a position where it islower than shown .inthat figure of the drawings to thereby increase the ,9 speed of operation of the mechanical timer.

Thetimer 9| is therefore of the adjustable speed type and I provide means for moving the oscillator I01 in accordance either with the desires of an operator or in accordance with the tem- 35 perature of the toaster, in order to-not only take care of light or dark toast, as may be desired, or different kinds of bread, but also to insure uniform .toasting of successive slices of bread with varying temperature of the toaster structure 0 as is now well understood in the art.

A speed adjusting member 9 of substantially L-shape has one end secured to shaft or pin 3 to which it is fixedly secured so that a clockwise turning movement thereof as seen in Figs. 1 and 2 of the drawings will cause an increase in the speed of the timer to thereby shorten the operating period of the toaster.

Means for acting upon the speed adjusting member 9 includes a shiftable bracket I2| guided by mounting pins I23 and I25 (see Fig.

2 of the drawings) this bracket being held by a bowed leaf spring I21 which is interlocked with pin I23. Bracket I2| includes a substantially horizontally extending portion I29 having'a forward portion I3I, which portion is provided with a lateral projection I33 adapted to fit into and move in a slot I35 .in one of the side plates of the timer, The inner edge of projection I33 is provided with teethwhich are engaged by a pinion I31 which pinion may be turned manually by a knob I39, the pinion I31 being mounted on a shaft I which may be supported by'a bearing bracket I43. It is therefore evident that aturning movement of knob I39 will result in vertical movement of bracket |2I.-

A stop pin I45 is provided in bracket I2I and a tension spring I41 engages arm III whereby to .bias oscillator '01 to its uppermost or slow posi tion, the position-of arm III and of speed adjusting member I I9 being of course dependent on the vertical position of bracket I2I.

A bimetal element I5| is preferably of the kind already disclosed and claimed in my copending application Ser. No. 127,100 flied February 23, 15

1937, and assigned to the same assignee as is the present application, is supported by an upand constructed that it will flex downwardly .with

increase in temperature of the toaster and of its own temperature and it is. therefore evident that as its own temperature increases, it will operatively engage speed adjusting member II9 but only after a predetermined change in temperature. It is so designed and constructed that it operates with a" negligible time lag, so that it follows temperature changes, to which it is responsive, faithfully and promptly.

The thermostat I5I is supported-in parallel spaced position relatively to the adjacent heating element comprising one or more plates 3| and resistor 33 and is screened from radiant heat emanating directly from the adjacent heating element by a thin plate I59 of thin sheet metal, such as iron or steel. This plate has a relatively small mass and thickness and is of such character that it will receive and transmit heat ra diated thereto with only a relatively small time lag. The plate I59 is therefore positioned between the heating element and the thermostat, but since the distance between the heating ele-- ment and the thermostat is relatively small the heat radiated to the thermostat by plate I59 will be at a temperature which is almost that of the radiant heat given ofi by the adjacent heating element itself. The baiile plate 29 is provided with an opening I6I therein and a portion of the bafile plate adjacent the opening may be shaped to overhang a part of the thermostat, this portion of the .bafile plate being indicated by I63 'and shown more particularly in Fig. 3 of the drawings. Plate I59 may be supported ,in any suitable or desired manner and I have shown it as being supported by portions I65 thereof riveted to baffle plate 29.

Since there is a space between the baille plate 29, which plate extends downwardly to base plate- I5 and upwardly to' within a very small distance of cover 2| and the adjacent heating element on one side of the bafile plate, and since there is a space between the baflle plate and the adjacent side wall of easing I9, it is evident that the thermostat will be subjected to closed circuit convection currents of heating air which currents are of different temperatures. The temperature of that convection current of heating air moving upwardly and downwardly between'baiile plate 23 and adjacent heating element will have ahigher temperature than does the convection current of heating air moving upwardly and downwardly between the baflle plate 23 and the side wall of casing I9. a e

The thermostat is therefore adapted to be subjected not only to secondary radiant heat caused by the main heating element of the toaster, the

temperature of this heat being substantially that or only slightly below that of the heating ems hating irom or radiated by the heating "element itself, but is also adapted to be subjected to convection currents of heating air of relatively high temperature.

As is evident from the :flgures of the drawings and the description of the structure embodied in the toaster assembly, a manual actuation of knob I33 will cause movement of bracket I2I in either an upwardly or a downwardly direction with action on speed adjusting arm" H3. Thus, if the Fig. 2 of the drawings, an operator can so turn knob I39 as to move bracket IZI, downwardly, stop pin I 45 causing turning movement of speed adjusting member H9 in a clockwise direction to thereby act upon oscillator I01 in such manner as to cause a change in speed of o ration of the timer and in this case an increase in the speed. s

It is further evident that the thermostat m is also simultaneously moved (e. g. in a downwardly direction) and that, for a constant temperature, its position relatively to speed adjusting member I I9 will remain the same during such movement of the bracket. Only after a predetermined change of temperature" will cam meinber I51 be caused to engage speed adjusting member H9 and cause an additional turning movement thereof in a clockwise direction to cause a further increase in speed of operation 01' the'timer and therefore a further decrease in the vtotal.

operating time of the toaster. K

As is already well known in the art, membe I83 hereinbefore described is adapted'to engage a pin I61 on the upper end of latch 83 after a certain length of time during which-carriage 41 has been moved upwardly by the action of rack bar 99 and pin IlII engaging below member I53. The outer and up er edge portion of member I03 is so shaped an positioned that it will cause movement of latch 89 to release slider 5i with which it was interlocked, this release of the latch permitting quick upward movement of the bread slice supports and of the sliders and opening of the control switch for the heating elements.

The device embodying my invention thus pro-1 vides first of all a novel form of heat source for a thermostatically operative element adapted to control the operating time of a mechanical timer,

initial position of bracket III is as shown in operation in accordance with the temperature of V the toaster. To effect this, I provide a secondary source of heat spaced a relatively small distance from the. main heating element of a toaster, this secondary source having a relatively small mass and heat storage capacity and being therefore adapted to follow very closely the temperature changes of'a heat source with tively associated.

F The device embodying my invention further provides a single means forvarying or adjusting the speed of a. variable speed mechanical timer in which the relative positions of a thermostat and a speed adjusting member remain constant for constant temperature conditions, thereby making it elasy to design and adjust the thermally-controlled timing mechanism to adapt it which it is operafor all of the operating conditions which a toaster of this kindmaymeet with in use.

The device embodying my invention provides a thermally-controlled mechanical timer in which the thermostat is normallyi'ree of outside'mechanical stress whereby the continuance of the 1 initial condition of the bimetal bar is ensured.

The thermostat is also shielded from anydraft oi. cooling air since it is located in a substantially enclosed space namely that defined by the heating element on the one side and the side wall of and the cover'lH.

(the casing on the otherside, the-bottom plate I5 The thermostat is so designed and constructed surface relatively to the pivotally mounted arm that it has a negligible time lag relatively to tembeing constant irrespective of the position of the perature changes to which it is responsive, therepivotally mounted arm relatively to the timer. by ensuring accurate and quick change in its 4. In a toaster the combination with a heating 5 position in accordance with temperature changes element and means to cause energization of the 5 controlling it. i I heating element, of means to effect deenergization Various modifications may be made in the deof the heating element including a variable speed vice embodying my invention without departing timer, an arm pivotally mounted on the timer and from the spirit and scope thereof and I desire, connected to cause a change in timer speed when therefore that only such limitations shall be moved, a manually-actuable bracket slidably l0 ,placcd thereon as are imposed by the prior art mounted on the timer, a stop member fixedly or are set forth in the appended claims. mounted on the bracket, a spring to bias said I claim as my invention: pivotally mounted arm against said stop member,

1. In' a toaster, the combination with an le whereby movement of the bracket causes a change tric heating element, a control switch for the in mer speed during Operation thereof and it 15 heating element biased to open position, a varib eta e ement s pp solely y Said bracket able speed mechanical timer having means theren rmally out of op rat ve en a ement w th s on connected to cause a change in timer speed armand subject to temperature changes in the when moved, means connected to simultaneously toast r o Operatively engaging said arm and effect closing of the swltchand, winding of the ary n t e me p d in a a c wit 20 timer and a latch adapted to hold the switch 1 g s of master e p in closed' position, of a thermally-actuable ele- A t a t as se i t in claim 4 in which the merit supported solely from the tim and gr manualiy-actuable bracket is effective to shift the tive to operatively engage the speed changing position of tliebimetal element relatively to the means after a predetermined change of temperatime! While maintaining unchanged the 25.

ture to control the speed of the ti r i accord. positions of the bimetal element and the pivotally ance with changes "in toaster temperatureand mounted a 1 Y means to simultaneously move th speed chang- 6'. In a toaster, the combination with an electric ing means and the thefmally-actuable el t heater and means to initiate a toasting operation, while maintaining constant their initial pos of means" to terminate a toasting operation in- 30 relatively to each other, 7 eluding a variable speed mechanical timer, an 2. In a toaster, the combination with an electric am on the timer biased In one direction and heating element,.a control switch for the heating nected to efiect a change timer Speed h element biased to er; o t o a vaflabfe Spegd moved, a single manually-actuabie bracket slid- 5 mechanical timer having a member thereon movably mounted on the time!" supported solely 3,

l able to cause a change in timer'sp'eed, means conthjereby and operamvely engaging a Qarm' to ne t ,t simultaneously fi t closing of limit movement thereof in said one direction and switch and winding of the timer and a latent abimetal element supported solely by said bracket o adapted to hold the switch in closed position, of in Position to be Subjected to master temperature I 40 a bimetal thermostat normally free from outside normally of engagemelnt f 40 mechanical stress, subject to toaster tempe t said arm, effective after a predetermined increase and adapted to operatively engage th Speed in temperature to operatively engage said arm changing member to control the timer speed in 'nd cause aspeed change in the timer, the amount accordance with changes in toaster temperature, of saidlincrease in temperature remaining the a bracket on the timer movable relatively thereto Same irrespective of the Position of e b k 45 constituting the sole support for the bimetal '7. 'In a toaster, the combination with an electhermostat and meansto effect movement of said 'trlc heater and means to initiate a toasting Operabracket on the timer to vary the position of the n, of means to terminate a toasting operation speed changing member and thereby the speed including a variable speed mechanical timer, an of the timer while maintaining th t arm on'the timer biased in one direction and con- {m thermostat normally free from outside mechanical nectd to effect a h e in timer speed when stress, g r moved, a single rrTanually-actuable bracket slid- 3. In a toaster, the combination with an electric ably mounted the Supported. solely heating element, a control switch for the heating thelfeby and operatively oengaging d arm to element biased to open position, v riabl speed ,lil'hit movement thereof in said one direction and as mechanical timep having thereon a, pivotall ebimetel e t pp r d s y y a d ck mounted arm connected to cause ahchamge in *1 inposition to be subjected totoaster temperature timer "speedrwhen moved, means c et d t and normally,out of operative engagement with simultaneously effect closing of the switch and saldarm, effective after a. predetermined increase 0 winding of the timer and latch means adapted to i tempera-tulle t0 p v y engage aid arm 50 hold the switch in closed position of a bimetal Q Cause a Speed 8 111 e t mer, the relathermostat subject to toaster temper'ature,a cam fi p sitions 0! the bimetal element and of the surface on thebimetal thermostat out of engageon time! remaining t e Sa e at conment with the pivotally mounted arm when the 1 Stunt t p I v bimtal thermosta is cold for engaging a -8. In a toaster, the combination with an electric ing said pivotall mounted a to o t pth f heater and means to initiate atoasting operation, 'timer speed in accordance with-changes in toaster 0% s, to terminate, oa t ng Operation intemperature, a member on the'timer movable I eluding a variable speed mechanical timer, an relatively thereto, constituting the sole support ,arin on the timer biased in one direction and confor the bimetal thermostat and having a stop ne'cted toef'fect a changein timer speed when 70 pin thereon engaged by'thepivotally mounted moved, a single manually-actuable bracket slidarm and means to efiect' movement of said mov-J ably mounted 'on the timer, supported solely able member on the timer to vary the position thereby and operatively engaging said arm to of said pivotally mounted arm and thereby-the limit movement thereof in saidone direction and 73 speed of the timer the cold position of thecam a bimetai element supported solely by said bracket 76 5,182,650 in position to be subjected to toaster temperature and normally free of externally applied mechanical stress and effective after a predetermined increase in temperature to operatively engage said arm and cause a speed changein the timer, the

amount of said increase in temperature remaining the same irrespective, of the position of the bracket. a

9. In a toaster, the combination with a heating element and means to cause energization of the when moved, a plurality of means supported solely from the timer and operable respectively manually and thermally for acting on said pivot- ,ally mounted arm to cause movement thereof, [said thermally-operable means being supported solely by said manually operable means.

.10. In a toaster, the combination with a heat- .ing element and means to cause energization of the heating element, of means to efiect deenergization of the heating element including a variable speed timer, an arm pivotally mounted on the timer and connected to cause a change in timer speed when moved, a plurality of means supported solely from the timer and operable respectively manually and thermally forfacting onlsaid pivotally mounted arm to cause movement thereof, said manually-operable means be-' ing effective to shift the position of the thermally-operable means relatively to the timer, the relative positions of the thermally-operable 5 means and of the pivotally mounted arm remaining the same during such shifting under constant temperature. l,

11. A device as set forth in claim 2 in which the bimetal thermostat consists of two integral bimetal bars of unequal lengths, normally coplanar, in side-by-side positions, the bracket supporting the free,end of the shorter bar to locate the longer bar nearer to the heating means than the shorter bar, the free endof the longer bar oving to operatively'engage said change speed ember on increase of temperature to cause in-v crease in timer speed with increase *in toaster temperature, the shorter b'ar acting to nullify in part the engaging movementof the longer bar to cause 'thethermally controlled timer to operate to obtain substantially-uniformly toasted slices of bread from the toaster. v

12. A device as set forth in claim 2 in which the bimetal thermostat consists of two integral 55 bimetal bars of unequal lengths, normally coplanar in side-by-side positions, the bracket supporting the free end of the shorter bar to locate the'longer bar nearer to the heating means than the shorter bar, the free end of the longer bar 60 moving to operatively engage said change speed.

member on increase of temperature to cause increase in timer speed with increase in toaster temperature, the shorter bar, being effective to cause the longer bar to operate with negligible time lag in response to changes iii toaster temperature; I

13. A deviceas set forth in claim 3 in which the bimetal thermostat consists of two normally coplanar, unitary bimetal bars of unequal lengths 7 and of substantially gishapesupportedby said member on the timer at only the free end of the shorter bar in such position relatively to the electric heating element that the longer arm is in a zone of higher temperature than is the 75 shorter arm, the cam surface being supportcd at the free end of the longer arm, the shorter arm counteracting in part the movement of the free end of the longer arm under temperature changes and cooperating with the cam surface as moved by the longer arm to ,cause successive slices \of bread to be toasted uniformly'by the toasterirrespective of changes of toaster temperature. v

14. In a toaster, the combination with a heating element and means to cause initiation of a toasting operatiomof means tocause termination of a toasting operation, including a variable speed timer, a single-arm lever pivotally mounted at one of its. ends on the timer and connected therewith to cause a change intimer speed when moved, a' manually-actuable means mounted, on

the timer and operatively engaging said lever arm at a predetermined distance from its pivot axis to cause movement thereof and a bimetal thermostat subject to' toaster temperature and effective when heated to operatively engage said lever arm at substantially said predetermined distance from its pivot axis to cause movement of said lever arm.

5. A toaster as set forth in claim 14 in which the bimetalthermostat is'supported solely by said manually-actuable means andin which a predetermined increase in temperature is necessary to causeoperative engagement between the bimetal thermostata'nd the lever arn'i.

16. A device as set-forth in claim 14 in which the bimetal thermostat is supported solely by -'said mariually-actuable means-and is normally out of operative engagement with said lever arm and in which the relative positions of the bimetal thermostat and its point of engagement on the lever arm remain unchanged duringmanu'al adjust'ment of the manually-actuable mea'nsat constant temperature.-

. 1'7. In a toaster,.the combination with a heating means and means to cause initiation of a slice of bread being toastedfof means to termi-' nate a toasting. operation includinga variable speed timer, a single-arm lever pivotally mounted at one of its ends on the timer and connected therewith to cause a change in timer speed when moved, a manually-adjustable bracket slidably mounted on the timer operatively engaging said lever arm at a predetermined distance from its pivot axis to cause movement of the lever arm and a bimetal thermostat supported solely from said bracket, normally free from externally applied mechanical stress and effective on predetermined increase of its temperature to operatively engage said lever arm at substantially said predetermined distance from its pivot axis to cause movement of said lever arm, said predeter mined increase of temperature being constant irrespective of the manually-effected adjustment of said lever arm'. r

18. In a toaster, the combination with an outer casing, a plurality of spaced heating elements in the casing, a pair of side walls positioned between the outer heating elements and the casing and means' to initiate a toasting operation,-ofv

means to terminate a toasting operation com prising a variable speedmechanical timer. a

single-arm lever-pivotally mounted on the timer and connected to cause a change in timer speedment, relatively close tosaid heating element and effective when heated to" operatively engage said single-arm lever to cause a change in wall and the heating element adjacent thereto cooperating to cause the thermostat to be subjected to a convection current of heating air of relatively high temperature when the heating element is energized.

ROBERT SARDESON. 

